Moreover, treatment of human keratinocytes with palmitic acid, a fatty acid mainly involved in obesity, induces the expression of Th17 cell-related cytokines with Regenerating islet-derived protein 3 gamma (Reg3γ), which results in epidermal hyperplasia, like psoriasis [27]. The gene discussed is REG3G; the disease is obesity due to melanocortin 4 receptor deficiency.